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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Stop detaches the debugger before shutdown hooks run, so JVM shutdown cannot be debugged","articleBody":"Since #1274 / microsoft/java-debug#579, pressing **Stop** on a launched Java program (with `\"console\": \"internalConsole\"`) sends SIGTERM through `vm.process().destroy()`, so shutdown hooks now run. However, the debugger detaches immediately afterwards, so breakpoints in shutdown hooks, `@PreDestroy` methods, Spring `SmartLifecycle.stop()`, etc. are never hit. As a result, the shutdown path of an application cannot be debugged from VS Code.\n\nThis is not a duplicate of #1274, #1585 or #1705. Those issues are about whether the JVM is terminated and whether the hooks run at all. This one is about the debug session staying attached while they run.\n\n##### Environment\n- Operating System: Linux Mint 22.1\n- JDK version: 21.0.7\n- Visual Studio Code version: 1.143.0\n- Java extension version: 1.59.2026102108 (pre-release)\n- Java Debugger extension version: 0.60.0\n\n##### Steps To Reproduce\n1. Create a program:\n   ```java\n   public class App {\n       public static void main(String[] args) throws Exception {\n           Runtime.getRuntime().addShutdownHook(new Thread(() -> {\n               System.out.println(\"hook start\");   // breakpoint here\n               System.out.println(\"hook end\");\n           }));\n           Thread.sleep(Long.MAX_VALUE);\n       }\n   }\n   ```\n2. Launch it with a `launch` configuration with `\"console\": \"internalConsole\"`.\n3. Set a breakpoint on the `hook start` line.\n4. Press **Stop**.\n\n##### Current Result\nThe debug session ends immediately. The hook runs (`hook start` / `hook end` may or may not reach the Debug Console), but the breakpoint is not hit.\n\n##### Expected Result\nThe first **Stop** asks the JVM to exit gracefully and keeps the debugger attached, so breakpoints in shutdown code are hit. The session ends when the JVM exits (VMDeath/VMDisconnect). A second **Stop** forcibly kills the JVM, as it does now. IntelliJ IDEA and Eclipse behave this way.\n\n##### Additional Informations\nCause: [`DisconnectRequestHandler.destroyDebugSession`](https://github.com/microsoft/java-debug/blob/main/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/DisconnectRequestHandler.java) does `terminate()` and then `detach()` in a `finally` block. `Process.destroy()` only sends the signal and does not wait for the process, so the debugger is gone before the hooks start. (Before microsoft/java-debug#626 the order was reversed explicitly.)\n\nDAP already supports this two-step behaviour through the [`terminate` request](https://microsoft.github.io/debug-adapter-protocol/specification#Requests_Terminate). If the adapter reports `supportsTerminateRequest: true`, VS Code sends `terminate` on the first Stop and `disconnect` on the next one. A possible implementation:\n\n- report `supportsTerminateRequest` in the `initialize` response;\n- handle `terminate` with `vm.process().destroy()` (when a `Process` is available) and do **not** detach; the existing VMDeath/VMDisconnect handling then sends `terminated` and ends the session;\n- keep the current `disconnect` behaviour (forced termination) for the second Stop and for restart.\n\nI have checked this approach locally with a small extension. It uses a `DebugAdapterTracker` to add `supportsTerminateRequest`, sends SIGTERM to the PID from the `processid` event, and lets the JVM exit on its own. With it, breakpoints in shutdown hooks are hit, and the session closes when the JVM exits.\n\nWith `\"console\": \"integratedTerminal\"` the adapter has no `Process` and falls back to `vm.exit(0)`, so the hooks do not run at all. That case may need the PID from the `runInTerminal` response, and could be handled separately.","author":{"url":"https://github.com/danilaslynko","@type":"Person","name":"danilaslynko"},"datePublished":"2026-10-22T11:11:27Z","url":"https://github.com/microsoft/vscode-java-debug/issues/1720"}